Index: trunk/src/gui_act.c
===================================================================
--- trunk/src/gui_act.c	(revision 31095)
+++ trunk/src/gui_act.c	(revision 31096)
@@ -623,8 +623,6 @@
 	return 0;
 }
 
-#define istrue(s) ((*(s) == '1') || (*(s) == 'y') || (*(s) == 'Y') || (*(s) == 't') || (*(s) == 'T'))
-
 static const char pcb_acts_EditLayer[] = "Editlayer([@layer], [name=text|auto=[0|1]|sub=[0|1])]\nEditlayer([@layer], attrib, key=value)";
 static const char pcb_acth_EditLayer[] = "Change a property or attribute of a layer. If the first argument starts with @, it is taken as the layer name to manipulate, else the action uses the current layer. Without arguments or if only a layer name is specified, interactive runs editing.";
 static fgw_error_t pcb_act_EditLayer(fgw_arg_t *res, int argc, fgw_arg_t *argv)
@@ -651,7 +649,7 @@
 		}
 		else if (strncmp(arg, "auto=", 5) == 0) {
 			interactive = 0;
-			if (istrue(arg+5))
+			if (rnd_istrue(arg+5))
 				ly->comb |= PCB_LYC_AUTO;
 			else
 				ly->comb &= ~PCB_LYC_AUTO;
@@ -659,7 +657,7 @@
 		}
 		else if (strncmp(arg, "sub=", 4) == 0) {
 			interactive = 0;
-			if (istrue(arg+4))
+			if (rnd_istrue(arg+4))
 				ly->comb |= PCB_LYC_SUB;
 			else
 				ly->comb &= ~PCB_LYC_SUB;
Index: trunk/src/librnd/core/misc_util.h
===================================================================
--- trunk/src/librnd/core/misc_util.h	(revision 31095)
+++ trunk/src/librnd/core/misc_util.h	(revision 31096)
@@ -83,4 +83,7 @@
 	b = __tmp__; \
 } while(0)
 
+#define rnd_istrue(s) (((s) != NULL) && ((*(s) == '1') || (*(s) == 'y') || (*(s) == 'Y') || (*(s) == 't') || (*(s) == 'T')))
+
+
 #endif
Index: trunk/src/obj_common.c
===================================================================
--- trunk/src/obj_common.c	(revision 31095)
+++ trunk/src/obj_common.c	(revision 31096)
@@ -161,8 +161,6 @@
 	}
 }
 
-#define istrue(s) ((*(s) == '1') || (*(s) == 'y') || (*(s) == 'Y') || (*(s) == 't') || (*(s) == 'T'))
-
 void pcb_obj_attrib_post_change(rnd_attribute_list_t *list, const char *name, const char *value)
 {
 	pcb_any_obj_t *obj = (pcb_any_obj_t *)(((char *)list) - offsetof(pcb_any_obj_t, Attributes));
@@ -210,7 +208,7 @@
 	}
 	else if ((obj->type == PCB_OBJ_TEXT) && (strcmp(name, "tight_clearance") == 0)) {
 		pcb_text_t *t = (pcb_text_t *)obj;
-		t->tight_clearance = value == NULL ? 0 : istrue(value);
+		t->tight_clearance = rnd_istrue(value);
 	}
 }